写CPLD时提示boundary－scan有错，啥原因呢？

写CPLD时提示boundary－scan有错，啥原因呢?
你的下载电缆没有接好或者是你的cpld jtag 电路有问题

写CPLD时提示boundary－scan有错，啥原因呢?
具体的提示为：
ERROR:JTag - Boundary scan chain has been improperly specified.Please check your configuration and re-enter the boundary-scan chain information.
Boundary-scan chain validated unsuccessfully.
ERROR:JTag - : The boundary-scan chain has not been declared correctly.
Verify the syntax and correctness of the device BSDL files, correct the files,
reset the cable and retry this command.